JPH09258244A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a point defect by providing an opening part of a protection film between a pixel electrode and a video signal line and constituting a liquid crystal display device so that the video signal line doesn't exist in the area of the opening part and the edge part of the pixel electrode is covered with the protection film. SOLUTION: Each pixel is arranged in a crossing area (area surrounded by four pieces of signal lines) between adjacent two pieces of scan signal lines (gate line or horizontal signal line)GL and adjacent two pieces of video signal lines (drain line, data line or vertical signal line)DL. Each pixel contains a thin film transistor TFT, a transparent pixel electrode ITO1 and a hold capacity element (additional capacity element) Cadd. The scan signal line GL is forked in the vicinity of the crossing area between the scan signal line GL and the video signal line DL. In this device, the protection film PSV1 is formed covering the edge part of the pixel electrode ITO1. Then, a slit shape opening SH is formed between the pixel electrode ITO1 and the adjacent video signal line DL on the protection film PSV1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a so-called active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art For example, an active matrix type liquid crystal display substrate is arranged in a matrix by laminating various materials on respective liquid crystal side surfaces of transparent glass substrates which are arranged to face each other with a liquid crystal interposed therebetween. Each pixel and an electronic circuit for operating each pixel are incorporated.

In the case of manufacturing such a liquid crystal display substrate, the transparent glass substrates are sequentially laminated with different material layers each having a predetermined pattern on their surfaces, and then they are arranged to face each other. The liquid crystal is sealed in.

Further, in this case, each material layer consisting of each pattern is formed by using a so-called photolithography technique, whereby finely processed pixels and electronic circuits are formed.

An application related to the present invention is Japanese Patent Application No. 7-39984, filed by the applicant of the present application.

As a known example in which a light shielding film is provided around the pixel electrode, there is JP-A-4-84125.

[0007]

However, the conventional liquid crystal display device manufactured as described above is not removed according to the pattern in the process of sequentially laminating various material layers having the predetermined pattern as described above. The material (usually referred to as foreign material) was often unavoidable.

FIG. 30 shows a pattern of one pixel of a conventional TFT liquid crystal display device. The reference numerals of the respective layers are the same as those in the examples described later, and thus the description thereof will be omitted.

FIG. 31 shows a cross section taken along the line AA 'of FIG. In the case of this pattern, as shown in FIG. 30, when a conductive substance such as Al or Cr of the drain wire material remains due to a foreign substance or the like,
As shown in FIG. 32, which is a cross section taken along the line BB ′ of FIG. 30, a pixel short-circuited due to a short circuit between the pixel electrode ITO 1 and the drain line DL becomes a point defect and causes a screen display failure.

The present invention has been made under such circumstances, and an object thereof is to provide a liquid crystal display device capable of preventing the occurrence of so-called point defects.

[0011]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

Means 1. A pixel electrode provided on the first substrate, a switch element, a video signal line for supplying a video signal to the pixel electrode via the switch element, and a protective film made of an insulating film for covering the video signal line. In the liquid crystal display device, the opening of the protective film is provided between the pixel electrode and the video signal line, the video signal line does not exist in the area of the opening, and the edge of the pixel electrode is formed. A liquid crystal display device, wherein a part is covered with the protective film.

Means 2. A pixel electrode provided on the first substrate, a switch element, a video signal line for supplying a video signal to the pixel electrode via the switch element, and a scan signal for controlling conduction / non-conduction to the switch element A liquid crystal display device comprising: a scanning signal line for controlling the scanning signal line; and a protective film made of an insulating film for covering the scanning signal line, wherein an opening of the protective film is provided between the pixel electrode and the scanning signal line. The liquid crystal display device is characterized in that there is no scanning signal line in the area of the portion and the edge portion of the pixel electrode is covered with the protective film.

Means 3. In the configuration according to means 1, the video signal line is made of an opaque metal film provided on the first substrate made of a transparent insulator, and an edge portion of the pixel electrode is made of the same material as the video signal line. A liquid crystal display device characterized in that the first light shielding film is covered with the first light shielding film, the first light shielding film is covered with the protective film, and the first light shielding film is not present in the region of the opening.

Means 4. In the structure according to the means 2, a first light-shielding film made of an opaque metal film provided on the first substrate made of a transparent insulator, and an edge portion of the pixel electrode made of the same material as the scanning signal line. The liquid crystal display device is characterized in that the first light-shielding film is covered with the protective film, and the first light-shielding film is not present in the region of the opening.

Means 5. In any one of the means 1 and 2, the second substrate, which is provided in a peripheral region of the pixel electrode and shields the switch element, is provided on a transparent second substrate facing the first substrate with a liquid crystal layer in between. Providing a light-shielding film,
The liquid crystal display device, wherein the second light-shielding film planarly covers the opening of the protective film.

Means 6. In any one of the means 1 and 2, the terminal is provided on the first substrate and electrically connected to the video signal line or the scanning signal line, and the terminal is exposed from the protective film. A liquid crystal display device comprising a transparent conductive film.

Means 7. In any one of the means 1 and 2, the drain terminal electrically connected to the video signal line is provided on the first substrate, and the drain terminal is formed of a metal film exposed from the protective film. And a transparent conductive film that covers the metal part.

Means 8. In any one of the means 1 and 2, a gate terminal electrically connected to the scanning signal line is provided on the first substrate, and the gate terminal is formed of a metal film exposed from the protective film. And a metal part
A liquid crystal display device comprising a transparent conductive film covering the metal portion.

According to the structure shown in the means 1, as shown in FIG. 1, since the protective film PSV1 between the drain line DL and the pixel electrode ITO1 is provided with the opening SH as shown in FIG. A liquid crystal display device with high yield and high productivity is provided.

In the case of the structure shown in the means 1, FIG. 8 and FIG.
As shown in FIG. 9 which is a cross section taken along line DD ′ of FIG.
Even if a conductive material such as l and Cr remains, the opening S is formed in the protective film PSV1 between the drain line DL and the pixel electrode ITO1.
Since H is open, if the conductive material (conductive material such as Al, Cr containing Al, Cr, etc.) is etched using the protective film PSV1 as a mask, as shown in FIGS. 10 and 11, the source and drain electrodes SD2, SD1, Since the additional capacitance electrode PL1 and the drain line DL are protected by the protective film PSV1 and only the foreign matter in the opening SH indicated by the line EE ′ is removed, the short circuit between the pixel electrode ITO1 and the drain line DL can be corrected.

Even if the gate material remains at the portion DD 'in FIG. 8, if the conductive material is etched using the protective film as a mask, the pixel electrode ITO1 adjacent to the pixel electrode ITO1.
You can fix shorts in between.

Therefore, it is possible to reproduce the liquid crystal display device having the point defect defect, and to provide the liquid crystal display device with high productivity.

Further, since the edge portion of the pixel electrode is covered with the protective film, the edge portion of the opening SH of the protective film is outside the pixel electrode, and the adhesiveness between the pixel electrode and the protective film is lowered, so that the opening portion is opened. It is possible to prevent the protective film from peeling from the edge of the SH.

According to the structure described in the means 2, since the opening of the protective film is provided between the pixel electrode and the scanning signal line and the scanning signal line does not exist in the area of the opening, the scanning signal line is Even if a pattern formation defect occurs during formation and the pixel electrode and the scanning signal line are short-circuited, the protective film may be used as an etching mask to etch the portion of the opening where the pixel electrode and the scanning signal line are short-circuited, as in the first method. Therefore, a defective TFT substrate due to a short circuit between the pixel electrode and the scanning signal line can be regenerated, and a liquid crystal display device with high manufacturing yield and high productivity is provided.

Further, since the edge portion of the pixel electrode is covered with the protective film, the edge portion of the opening portion of the protective film is outside the pixel electrode, and the adhesiveness between the pixel electrode and the protective film is lowered, so that the opening portion is not covered. It is possible to prevent the protective film from peeling from the edge.

According to the structure of the means 3, the edge portion of the pixel electrode is covered with the first light shielding film made of the same material as the video signal line, the first light shielding film is covered with the protective film, and the protective film is formed. Since the first light-shielding film does not exist in the area of the opening, the same effect as that of the means 1 can be obtained, and at the same time, the first light-shielding film can be obtained.
The light-shielding film has a function of a black matrix that blackens the periphery of the pixel electrode, and an effect of improving display contrast can be obtained.

Further, since the first light-shielding film is provided on the same TFT substrate as the pixel electrode, the interlayer alignment accuracy between the first light-shielding film and the pixel electrode becomes good, and the overlap margin between the first light-shielding film and the pixel electrode is reduced. Thus, a liquid crystal display device having a high aperture ratio and a bright display screen can be provided.

According to the structure of means 4, the edge portion of the pixel electrode is covered with the first light shielding film made of the same material as the scanning signal line, the first light shielding film is covered with the protective film, and the protective film is formed. Since the first light-shielding film does not exist in the area of the opening, the same effect as that of the means 1 can be obtained, and at the same time, the first light-shielding film can be obtained.
The light-shielding film has a function of a black matrix that blackens the periphery of the pixel electrode, and an effect of improving display contrast can be obtained.

Further, since the first light-shielding film is provided on the same TFT substrate as the pixel electrode, the accuracy of interlayer alignment between the first light-shielding film and the pixel electrode becomes good, and the overlap margin between the first light-shielding film and the pixel electrode is reduced. Thus, a liquid crystal display device having a high aperture ratio and a bright display screen can be provided.

According to the structure shown in the means 5, the transparent second substrate (counter substrate) which faces the TFT substrate through the liquid crystal layer.
Since the second light-shielding film provided above covers the opening of the protective film in a plane, the liquid crystal layer of the liquid crystal layer is generated because the alignment treatment is not sufficiently performed by rubbing at the opening of the protective film. This has the effect of making the poorly oriented portion (domain) invisible, and improves the display contrast.

According to the structure of the means 6, the terminal electrically connected to the video signal line or the scanning signal line is provided on the TFT substrate, and the terminal is made of the transparent conductive film exposed from the protective film. Because of the configuration, there is no problem that the terminals are also removed in the step of removing the video signal lines or the scanning signal lines remaining in the openings of the protective film by etching.

According to the structure described in the means 7, the drain terminal electrically connected to the video signal line is provided on the TFT substrate, and the drain terminal is a metal portion formed of the metal film exposed from the protective film. Since the transparent conductive film covers the metal part, the metal part of the drain terminal is not removed in the step of removing the video signal line or the scanning signal line remaining in the opening of the protective film by etching. Moreover, since the drain terminal is a laminated film of the metal part and the transparent conductive film, the electric resistance of the terminal part is low and the connection between the external circuit and the video signal line is good.

According to the structure shown in the means 8, the gate terminal electrically connected to the scanning signal line is provided on the TFT substrate, and the gate terminal is the metal portion formed of the metal film exposed from the protective film. Since the transparent conductive film covering the metal portion is formed, the metal portion of the gate terminal is not removed in the step of removing the video signal line or the scanning signal line remaining in the opening of the protective film by etching. Moreover, since the gate terminal is a laminated film of the metal part and the transparent conductive film, the electric resistance of the terminal part is low and the connection between the external circuit and the scanning signal line is good.

[0035]

The objects and features of the present invention will be apparent from the following description with reference to the drawings.

Example 1 << Active Matrix Liquid Crystal Display >>
An embodiment in which the present invention is applied to an active matrix type color liquid crystal display device will be described. In the drawings described below, those having the same function are given the same reference numerals,
The description of the repetition is omitted.

<< Overall Configuration of Liquid Crystal Display Module >> FIG.
[Fig. 3] is an exploded perspective view showing each component of the liquid crystal display module MDL.

SHD is a shield case made of a metal plate (also called a metal frame), WD is a display window and INS1.
To 3 are insulating sheets, PCB1 to 3 are circuit boards (PCB1
Is a drain side circuit board, PCB2 is a gate side circuit board,
PCB3 is an interface circuit board), JN1 to 3 are joiners for electrically connecting the circuit boards PCB1 to PCB3, TCP1 and TCP2 are tape carrier packages,
PNL is a liquid crystal display panel, GC is a rubber cushion, IL
S is a light-shielding spacer, PRS is a prism sheet, SPS is a diffusion sheet, GLB is a light guide plate, RFS is a reflection sheet, and M is
CA is a lower case (molded case) formed by integral molding, LP is a fluorescent tube, LPC is a lamp cable, G
B is a rubber bush that supports the fluorescent tube LP, and the members are stacked in a vertical arrangement as shown in the figure to assemble the liquid crystal display module MDL.

The module MDL includes a lower case MCA,
The shield case SHD has two types of storage / holding members. Insulating sheets INS1-3, circuit boards PCB1-3,
The module MDL is formed by combining a metal shield case SHD containing and fixing the liquid crystal display panel PNL and a lower case MCA containing a backlight BL including a fluorescent tube LP, a light guide plate GLB, a prism sheet PRS, and the like. Assembled.

<< Outline of Matrix Unit >> FIG. 1 is a plan view showing one pixel and its periphery of a liquid crystal display panel of an active matrix type color liquid crystal display device to which the present invention is applied.
2 is a view showing a cross section taken along a line 2-2 in FIG. 1 (a cross sectional view showing adjacent transparent pixel electrodes and video signal lines), FIG.
1 is a cross-sectional view taken along the line 3-3 in FIG. 1 (a cross-sectional view showing a thin film transistor of one pixel and its periphery), and FIG. 4 is a cross-sectional view taken along the line 4-4 in FIG. FIG.

As shown in FIG. 1, each pixel has two adjacent scanning signal lines (gate line or horizontal signal line) GL and two adjacent video signal lines (drain line, data line or vertical signal line). ) It is arranged in an area intersecting with DL (area surrounded by four signal lines). Each pixel includes a thin film transistor TFT, a transparent pixel electrode ITO1 and a storage capacitor element (additional capacitor element) Cadd. The scanning signal line GL is bifurcated near the intersection with the video signal line DL. This is because when one of the two lines of this part is short-circuited with the video signal line DL, this is cut with a laser, and the other one (not cut) line does not become a line defect and is normal. This is to make it work.

Here, particularly in this embodiment, the protective film PSV1 is formed so as to cover the edge portion of the pixel electrode ITO1, and the protective film PSV1 and the video signal line DL adjacent to the pixel electrode ITO1 are formed. A slit-shaped opening SH is formed between them.

The slit-shaped opening SH is formed in the pixel electrode IT.
This is an opening for removing the conductive foreign matter adhered between O1 and the wiring layer (video signal line DL) adjacent to the pixel electrode ITO1, and the removal method will be described in the section “Manufacturing Method”. It will be described later.

In this embodiment, the slit-shaped opening S
In the figure, H is the pixel electrode ITO1 and drain line D
Although it is formed only between L and L, the present invention is not limited to this and may be formed between the pixel electrode ITO1 and the gate line GL, and the entire periphery of the pixel electrode ITO1 is exposed. It goes without saying that the slit-shaped opening SH may be formed in such a shape.

As shown in FIG. 3, a thin film transistor TFT and a transparent pixel electrode ITO1 are formed on the side of the first transparent glass substrate SUB1 based on the liquid crystal layer LC, and the second transparent glass substrate SUB1 is formed.
On the transparent glass substrate SUB2 side of the color filter FI
L, a black matrix pattern BM for shading is formed. Silicon oxide films SIO formed by dipping or the like on both surfaces of the transparent glass substrates SUB1 and SUB2
Is provided.

On the inner (liquid crystal LC side) surface of the second transparent glass substrate SUB2, a light shielding film BM and a color filter F are provided.
IL, protective film PSV2, common transparent pixel electrode ITO2 (C
OM) and the upper alignment film ORI2 are sequentially stacked. POL1 and POL2 are polarizing plates formed on the outer surfaces of the transparent glass substrates SUB1 and SUB2, respectively.

PD1 and PD2 are retardation films for enlarging the viewing angle. By attaching them, the viewing angle in the vertical scanning direction is changed from 45 ° to 90 ° and the viewing angle in the horizontal scanning direction is changed from 90 ° to 170 °. Spread every time.

Regarding the retardation film, “a film for liquid crystal capable of enlarging the viewing angle without sacrificing the brightness has appeared”, Nikkei Microdevice, January 1996, p. 1
67-page 169.

<< Thin Film Transistor TFT >> Next, FIG.
3, the configuration on the first transparent glass substrate SUB1 side will be described in detail. When a positive bias (scanning signal) is applied to the scanning signal line GL, the channel resistance between the source and the drain decreases, and when the bias (scanning signal) is zero, the channel resistance increases.

One thin film transistor TFT for each pixel
Is provided. The thin film transistor TFT is formed on the scanning signal line GL, as shown in FIG. The thin film transistor TFT has a gate electrode (scanning signal line GL),
The anodic oxide film AOF of the scanning signal line GL and the insulating film GI of silicon nitride are coated, and the AOF and GI form a gate insulating film. I-type (intrinsic, int
i-type semiconductor layer A made of amorphous silicon (Si) which is not doped with a conductive type determining impurity
S, a pair of source electrode SD1 and drain electrode SD2. It should be understood that the source and drain are originally determined by the bias polarity between them, and the polarity is inverted during operation in the circuit of this liquid crystal display device, so it should be understood that the source and drain are switched during operation. However, in the following description, one is fixed and the other is fixed as a drain for convenience.

<< Gate Electrode (Scanning Signal Line GL) >> In this example, the scanning signal line GL is formed of a single-layer first conductive film g1. An aluminum (Al) film formed by sputtering, for example, is used as the first conductive film g1, and an anodic oxide film AOF of Al is provided thereon in a self-aligned manner.

<< Insulating Film GI >> The insulating film GI is used as a gate insulating film for applying an electric field from the scanning signal line GL to the semiconductor layer AS together with the anodized film AOF in the thin film transistor TFT. As the insulating film GI, for example, a silicon nitride film formed by plasma CVD is selected,
With a thickness of 120 nm to 270 nm (22 in this embodiment).
0 nm). In this example, the insulating film GI is formed on the thin film transistor TFT portion, the storage capacitor Cadd, the source electrode SD1, the drain electrode SD2 portion, and the video signal line DL portion, and the drain electrode SD2.
And a pattern along a part of the video signal line DL.

<< i-type semiconductor layer AS >> i-type semiconductor layer AS
Is formed in the thin film transistor TFT portion and the source electrode SD1 and drain electrode SD2 portion in this example, and is patterned in a shape along the drain electrode SD2 and a part of the video signal line DL. The semiconductor layer AS is made of amorphous silicon and has a thickness of 20 nm to 220 nm (about 200 nm in this embodiment). The layer d0 is a phosphorus (P) -doped N ⁺ -type amorphous silicon semiconductor layer for ohmic contact, where the i-type semiconductor layer AS is present on the lower side and the conductive layer d2 (d3) is present on the upper side. Only left.

The i-type semiconductor layer AS is an anodic oxide film AOF for insulation isolation at the intersection of the scanning signal line GL and the video signal line DL, and the intersection of GL and the source electrode SD1, the drain electrode SD2 and the storage capacitor Cadd. , Insulating film GI
At the same time, line defects due to short circuits are reduced. Further, the N ⁺ type amorphous silicon d0 and the i type semiconductor layer A are extended from below the source electrode SD1 onto the transparent conductive film ITO1 (d1).
Although S and the insulating film GI are formed, the source electrode SD1 is connected to the transparent conductive film ITO1 (d1) without disconnection as described later. Furthermore, even if the source electrode SD1 and the drain electrode SD2 are not properly patterned and these electrodes remain on the scanning signal line GL only in the portion of the anodic oxide film AOF, the anodic oxide film AO is not formed.
Even an F single film has a predetermined withstand voltage and can prevent a short circuit. This is also one of the features of the present invention.

On the other hand, in this embodiment, the intersection of the scanning signal line GL and the video signal line DL and the thin film transistor TF.
The semiconductor layer AS and the insulating film GI below the video signal line DL in the T portion extend on the transparent pixel electrode ITO1, and the video signal line D
It serves to insulate and separate L from the transparent pixel electrode ITO1. This is also one of the features of the present invention. Therefore, even if the distance between the video signal line DL and the transparent pixel electrode ITO1 is narrowed to form a bright liquid crystal display device with a high aperture ratio, a point defect due to a short circuit between the video signal line DL and the transparent pixel electrode ITO1 (d1). Can be prevented.

<< Transparent Pixel Electrode ITO1 >> Transparent Pixel Electrode I
TO1 constitutes one of the pixel electrodes of the liquid crystal display section. The transparent pixel electrode ITO1 is connected to the source electrode SD1 of the thin film transistor TFT. This transparent pixel electrode ITO1
Is composed of a first conductive film d1, and the first conductive film d1 is a transparent conductive film (I
It is made of ndium-Tin-Oxide ITO (nesa film) and is formed to a thickness of 100 nm to 200 nm (about 140 nm in this embodiment).

<< Source electrode SD1, Drain electrode SD
2 >> Each of the source electrode SD1 and the drain electrode SD2 is composed of a second conductive film d2 in contact with the N ⁺ type semiconductor layer d0 and a third conductive film d3 formed thereon.

The second conductive film d2 is a chromium (Cr) film formed by sputtering and is formed to a thickness of 50 to 100 nm (about 60 nm in this embodiment). Cr film is N ⁺
Adhesion with the type semiconductor layer d0 is improved, and the third conductive film d3
Al is used for the purpose of preventing diffusion of Al into the N ⁺ type semiconductor layer d0 (so-called barrier layer). As the second conductive film d2, in addition to the Cr film, a high melting point metal (Mo, Ti, T
a, W) film, refractory metal silicide (MoSi2, Ti)
Si2, TaSi2, WSi2) film may be used.

The third conductive film d3 is formed by sputtering Al containing Si to a thickness of 300 to 500 nm (in this embodiment,
About 300 nm). The Al film has less stress than the Cr film and can be formed to have a large film thickness.
It has the functions of reducing the resistance values of the source electrode SD1, the drain electrode SD2, and the video signal line DL, and ensuring that the step difference caused by the scanning signal line GL is overcome (step coverage is improved).

The source electrode SD1 and the drain electrode SD2 are laminated films of the second conductive film d2 and the third conductive film d3. In the case of a relatively small liquid crystal display device, they are refractory metals such as Cr film. Only the second conductive film may be used.
In that case, it is necessary to increase the film thickness to about 180 nm.

After patterning the second conductive film d2 and the third conductive film d3 with the same mask pattern, the N ⁺ type semiconductor layer is formed by using the same mask or by using the second conductive film d2 and the third conductive film d3 as a mask. d0 is removed. That is, the N ⁺ semiconductor layer d0 remaining on the i-type semiconductor layer AS is self-aligned except for the second conductive film d2 and the third conductive film d3. At this time, since the N ⁺ type semiconductor layer d0 is etched so that the entire thickness thereof is removed,
The surface of the i-type semiconductor layer AS is slightly etched, but the degree thereof may be controlled by the etching time.

<Video Signal Line (Drain Line) DL> The video signal line DL is composed of the second conductive film d2 and the third conductive film d3 in the same layer as the source electrode SD1 and the drain electrode SD2, or
Alternatively, it is composed of only the second conductive film d2.

<< Protective Film PSV1 >> Thin Film Transistor TF
A protective film PSV1 is provided on the T and the transparent pixel electrode ITO1. The protective film PSV1 is formed mainly for protecting the thin film transistor TFT from moisture and the like,
Use one with high transparency and good moisture resistance. The protective film PSV1 is formed of, for example, a silicon oxide film or a silicon nitride film formed by a plasma CVD apparatus, and has a thickness of 600.
It is formed with a thickness of about nm. The protective film is generally formed by a vacuum device such as plasma CVD, but it may be formed by coating an organic material such as epoxy resin, and the throughput is improved.

The protective film PSV1 is formed on the pixel electrode I as shown in FIG. 2 which is a cross section taken along line 2-2 of FIG.
It can be confirmed that the slit-shaped opening SH is formed around TO1.

<< Light-shielding film BM >> Second transparent glass substrate SU
A light shielding film BM is provided on the B2 side so that external light or backlight light does not enter the i-type semiconductor layer AS. The closed polygonal outline of the light-shielding film BM shown in FIG.
The inside thereof shows an opening in which the light shielding film BM is not formed. The light-shielding film BM is formed of, for example, an aluminum film or a chromium film having a high light-shielding property against light, and in this embodiment, the chromium film is formed by sputtering to a thickness of about 130 nm.

Therefore, i of the thin film transistor TFT
At least the so-called channel region between the source electrode SD1 and the drain electrode SD2 in the type semiconductor layer AS is sandwiched by the upper and lower light-shielding films BM and the large scanning signal lines GL so that external natural light or backlight light does not hit. The light-shielding film BM is formed in a lattice shape around each pixel (so-called black matrix), and the effective display area of one pixel is partitioned by this lattice. Therefore, the contour of each pixel is made clear by the light shielding film BM, and the contrast is improved. That is, the light blocking film BM has two functions of blocking the i-type semiconductor layer AS and serving as a black matrix.

In the present invention, the light shielding film BM is the protective film PS.
It is provided so as to cover the opening SH of V1. Therefore, the defective alignment of the liquid crystal layer LC generated in the opening SH is caused by the light shielding film B.
It is hidden by M and cannot be seen, and the display contrast is not lowered.

The alignment of the liquid crystal layer LC is generally the alignment film ORI1.
Is rubbed with a cloth-rolled roller or the like, which is a so-called rubbing treatment.

However, as shown in FIG. 2, the protective film PSV1
Since the opening SH is a deep groove, the rubbing roller does not reach it, and the alignment film ORI1 in that portion is not sufficiently aligned.

Therefore, the opening SH of the protective film PSV1 is liable to cause misalignment. Therefore, it is necessary to cover the part with the light shielding film BM to prevent the transmitted light from leaking.

The light-shielding film BM is also formed in a frame shape in the peripheral portion of the liquid crystal display panel, and its pattern is formed continuously with the pattern of the matrix portion shown in FIG. 1 in which a plurality of dots-like openings are provided. The light-shielding film BM in the peripheral portion has a seal portion S
It is extended to the outside of L to prevent leaked light such as reflected light due to a mounting machine such as a personal computer from entering the matrix portion. On the other hand, the light-shielding film BM is held inside about 0.3 to 1 mm from the edge of the substrate SUB2, and is formed so as to avoid the cut region of the substrate SUB2.

<< Color Filter FIL >> The color filter FIL (see FIGS. 2 and 3) has red, green, and
The stripes are formed by repeating blue. The color filter FIL is formed to be large so as to cover all of the transparent pixel electrode ITO1, and the light shielding film BM is formed inside the peripheral portion of the transparent pixel electrode ITO1 so as to overlap with the edge portions of the color filter FIL and the transparent pixel electrode ITO1. There is.

The color filter FIL can be formed as follows. First, the dyeing base material such as acrylic resin is removed from the surface of the second transparent glass substrate SUB2. After this,
The dyed base material is dyed with a red dye and subjected to a fixing treatment to form a red filter R. Next, a green filter G and a blue filter B are sequentially formed by performing a similar process.

<< Protective Film PSV2 >> The protective film PSV2 is provided to prevent the dye of the color filter FIL from leaking to the liquid crystal LC. The protective film PSV2 is formed of, for example, a transparent resin material such as an acrylic resin or an epoxy resin.

<< Common Transparent Pixel Electrode ITO2 >> The common transparent electrode ITO2 (see FIGS. 2 and 3) is a transparent pixel electrode ITO provided for each pixel on the first transparent glass substrate SUB1 side.
1. The optical state of the liquid crystal LC faces each pixel electrode IT.
It changes in response to a potential difference (electric field) between O1 and the common transparent pixel electrode ITO2. A common voltage Vcom is applied to the common transparent pixel electrode ITO2. In this embodiment, the common voltage Vcom is the video signal line D
It is set to an intermediate DC potential between the minimum level video signal Vdmin applied to L and the maximum level video signal Vdmax, but when it is desired to reduce the power supply voltage of the integrated circuit used in the video signal drive circuit to about half, The AC voltage may be applied.

<< Structure of Storage Capacitance Element Cadd >> The storage pixel element ITO1 is formed so as to overlap the adjacent scanning signal line GL at the end opposite to the end connected to the thin film transistor TFT. It is electrically connected to one electrode PL2 of Cadd. As is apparent from FIG. 4, the storage capacitor element Cadd has a transparent pixel electrode I
Source electrode SD1 and drain electrode S connected to TO1
The second conductive film d2 and the third conductive film d3 which are the materials of D2
And the adjacent scanning signal line G as one electrode PL2.
L is the other electrode PL1.

The dielectric film of the storage capacitor Cadd is
It is composed of an anodized film AOF and an insulating film GI used as a gate insulating film of the thin film transistor TFT.

<< Manufacturing Method >> Next, FIG. 6 shows cross sections 3-3 and 2-2 of the pixel shown in FIG. 1, and FIG.
In addition, in FIG. 6, the left character is an abbreviation for the process name,
The left side shows the portion showing the 3-3 cross-sectional shape of FIG. 1, and the right side shows the flow of processing seen from the cross-sectional shape of 2-2 of FIG. Except for the process B, the processes A to G are divided corresponding to each photo (photo) process, and each cross-sectional view of each process shows a stage where the processing after the photo process is completed and the photoresist is removed. In the present description, the photographic (photo) processing means a series of operations from application of photoresist to selective exposure using a mask to development thereof, and repeated description will be omitted. Description will be given below according to the divided steps.

Step A After the silicon oxide films SIO are formed on both surfaces of the first transparent glass substrate SUB1 made of 7059 glass (trade name) by dipping, baking is performed at 500 ° C. for 60 minutes. Although this SIO film is formed in order to alleviate the surface irregularities of the glass substrate SUB1, this step can be omitted if the irregularities are small.

Next, the transparent glass substrate SUB1 is washed.
Al-Ta, Al-Ti-Ta, A with a film thickness of 300 nm
A second conductive film g2 made of l-Pd or the like is provided by sputtering. After the photo-treatment, the first conductive film g1 is selectively etched with a mixed acid solution of phosphoric acid, nitric acid and glacial acetic acid to form the gate electrode (GL) of the thin film transistor TFT and one electrode PL1 of the storage capacitor Cadd.

Step B After the resist was directly drawn (after the above-mentioned anodic oxidation pattern AO was formed), 3% tartaric acid was added to the pH of 6.25 ± by an ammonia.
The solution adjusted to 0.05 is 1: 1 with ethylene glycol solution.
The substrate SUB1 is dipped in an anodizing solution composed of a solution diluted to 9 to adjust the formation current density to 0.5 mA / cm 2 (constant current formation). Next, anodic oxidation is performed until the formation voltage 125 V necessary for obtaining a predetermined Al ₂ O ₃ film thickness is reached. After that, it is desirable to hold this state for several tens of minutes (constant voltage formation). This is important for obtaining a uniform Al ₂ O ₃ film. Thereby, the conductive film g1
Are anodized to have a film thickness of 17 in a self-aligned manner on the scanning signal line (gate line) GL and one electrode PL1 (g1) of the storage capacitor Cadd and on the side surface of each electrode.
The 5 nm anodic oxide film AOF is formed, and a part of the gate insulating film of the thin film transistor TFT and the storage capacitor element Ca are formed.
It becomes a dielectric film of dd. At this time, the film thickness of the gate electrode GL is about 175 nm.

Step C A conductive film d1 made of an ITO film having a thickness of 140 nm is provided by sputtering. After the photo process, the conductive film d1 is selectively etched with a mixed acid solution of hydrochloric acid and nitric acid as an etching solution to form the uppermost layer of the gate terminal GTM and the drain terminal DTM, and the transparent pixel electrode ITO1.

Step D Ammonia gas, silane gas and nitrogen gas are introduced into the plasma CVD apparatus to form a Si nitride film having a thickness of 220 nm, and silane gas and hydrogen gas are introduced into the plasma CVD apparatus to obtain i having a thickness of 200 nm. After forming the type amorphous Si film, hydrogen gas and phosphine gas are introduced into the plasma CVD apparatus to form an N ⁺ type amorphous Si film having a film thickness of 30 nm. This film formation is continuously performed by changing the reaction chamber in the same CVD apparatus.

After the photo processing, the N ⁺ type amorphous Si film and the i type amorphous Si film are etched using SF6 and CCl4 as a dry etching gas.

Step E Next, the Si nitride film is etched using SF6.
Of course, the N ⁺ -type amorphous Si film, the i-type amorphous Si film and the Si nitride film may be continuously etched with SF6 gas.

Step F A second conductive film d2 made of Cr having a film thickness of 60 nm is provided by sputtering, and Al- having a film thickness of 300 nm is formed.
A third conductive film d3 made of Pd, Al-Si, Al-Ta, Al-Ti-Ta or the like is provided by sputtering.
After the photo-treatment, the third conductive film d3 is etched with the same liquid as the process A, and the second conductive film d2 is etched with a second cerium ammonium nitrate solution to form the video signal line DL, the source electrode SD1 and the drain electrode SD2. To do. At the same time, the other electrode PL2 of the storage capacitor Cadd is provided. In addition, i is provided between the gate insulating film GI and the electrode PL2.
Since the island-shaped pattern IL including the n-type semiconductor layer AS and the N ⁺ -type amorphous Si layer d0 is provided, the side wall of the gate insulating film GI has a tapered slope, and the electrode PL2 crosses over the gate insulating film GI. The probability of disconnection of the electrode PL2 decreases.

Next, a dry etching apparatus is equipped with SF6,
By introducing CCl4 and etching the N ⁺ -type amorphous Si film, the N ⁺ -type semiconductor layer d0 between the source and the drain is selectively removed.

Step G Ammonia gas, silane gas, and nitrogen gas are introduced into the plasma CVD apparatus to form a Si nitride film having a thickness of 600 nm. After that, apply photoresist and after exposure and development,
By etching using SF6 as a dry etching gas, the protective film PSV1 is patterned.

At this point, the pattern of the opening SH is formed in the protective film PSV1.

As the protective film, not only a SiN film formed by CVD but also an organic material can be used.

Step H Next, after the protective film PSV1 is formed in this way, in this embodiment, the conductive film etching step shown in FIGS. 10 to 11 is performed. The reason for this is that the pixel electrode ITO
1 and the wiring layer (scanning signal line GL or video signal line DL) adjacent to the pixel electrode ITO1 adheres to the pixel electrode ITO1 due to adhesion of conductive foreign matter (including the residue of the semiconductor layer AS). This is to prevent the occurrence of point defects at the manufacturing stage.

FIG. 8 is a diagram after the protective film PSV1 is formed. Here, in the worst case, the pixel electrode IT is shown.
O1 has a foreign material A (a laminated film of Si-containing Al and Cr in this embodiment) formed of a metal film attached between the adjacent video signal lines DL on the right side of the drawing, and the electrical signal is electrically connected to the video signal lines DL. It is assumed that a short circuit has occurred. A cross section taken along the line DD ′ of FIG. 8 is shown in FIG. 9.

At this point, the manufacturer does not need to be aware of the presence of this foreign substance. This is because the conductive film etching step (step H) is performed on the assumption that foreign matter is present.

First, the mixed film of phosphoric acid, nitric acid and glacial acetic acid was used to selectively etch the third conductive film d3 made of Al, which remained as a foreign matter, and then was etched with a cerium ammonium nitrate solution to remain as a foreign matter. The second conductive film d2 made of Cr is selectively etched to completely remove the conductive foreign matter in the region of the opening SH of the protective film PSV1 as shown in FIG.

After that, the photoresist mask on which the pattern of the protective film PSV1 is formed is removed.

By leaving the photoresist mask on which the pattern of the protective film PSV1 is formed up to the conductive film etching step (process H), the protective film is prevented from being roughened by the conductive film etching liquid or etching gas. You can

When the protective film and the conductive film can be selectively etched, the conductive film etching process (process H) is performed after the photoresist mask is removed at the time of the pattern forming process (process G) of the protective film PSV1. May be.

By passing through this conductive film etching step (step H), the drain line DL and the pixel electrode ITO1 are electrically separated from each other, and a short circuit between the drain line DL and the pixel electrode ITO1 causes a point defect defect in the liquid crystal display device. Are reproduced and become a non-defective liquid crystal display device having no point defect defect.

Further, as shown in FIGS. 1 and 2, the protective film P
Since the SV1 covers the edge portion of the pixel electrode ITO1, the protective film PSV1 does not adhere to and peel off the substrate SUB1 outside the pixel electrode ITO1 even when the adhesion between the protective film PSV1 and the pixel electrode ITO1 is not good. .

<< Terminal Structure >> In carrying out the present invention, it is necessary to consider a terminal for electrical connection with an external circuit.

Since the terminals are exposed from the protective film PSV1, it is necessary to have a structure which is not removed in the conductive film etching step (step H) in carrying out the present invention.

FIG. 12 shows the structure of the gate terminal GTM in the protective film forming step (step G), showing the opening SH of the protective film at that time.
It is the figure shown in comparison with the structure of the vicinity.

After that, the drain line DL and the pixel electrode ITO1 are electrically separated by passing through a conductive film etching step (step H).

In the present invention, as shown in FIG. 12, the gate terminal GTM electrically connected to the gate line GL is formed of the same transparent conductive film d1 as the pixel electrode. Therefore, since the transparent conductive film has etching selectivity with respect to the metal film which is the material of the drain line DL and the gate line GL, there is no problem of removal in the conductive film etching step (step H).

Further, in the present invention, as shown in FIG. 12, the gate terminal GTM has a laminated structure of a transparent conductive film and a metal film g1 which is a material of the gate line GL. Therefore, the electric resistance can be reduced as compared with the case where the gate terminal GTM is formed only by the transparent conductive film, and the electric connection with the external circuit is improved. Moreover, since the metal film g1 is covered with the transparent conductive film d1 and has no exposed portion, there is no problem of removal in the conductive film etching step (process H).

The same can be said for the drain terminal DTM electrically connected to the drain line DL as described above.

Similar to FIG. 12, FIG. 13 is a diagram showing the structure of the drain terminal DTM in the protective film forming step (step G) in comparison with the structure in the vicinity of the opening SH of the protective film at that time. .

The drain line DL is a metal film g1 made of the same material as the gate line GL in the portion where the gate insulating film GI is removed.
Is electrically connected to the transparent conductive film d1. Then, the connection portion thereof is covered with the protective film PSV1.
Therefore, since the portion of the drain terminal DTM exposed from the protective film PSV1 and exposed to the outside air is the transparent conductive film d1, the drain terminal D in the conductive film etching step (step H).
There is no problem that TM is removed. In addition, the drain terminal DTM
Also, since the transparent conductive film d1 and the metal film g1 have a laminated structure, the electric resistance of the terminal can be reduced, and the electrical connection with the external circuit is improved.

[Embodiment 2] << Outline of Matrix Part >> FIG. 14 is a plan view showing one pixel and its periphery of an active matrix type liquid crystal display panel for explaining the second embodiment of the present invention, FIG. Figure 1
4 is a view showing a cross section taken along a line 2-2 in FIG. 4 (a cross sectional view showing adjacent video signal lines and transparent pixel electrodes), and FIG.
4 is a cross-sectional view taken along the line 3-3 of FIG. 4 (a cross-sectional view showing a thin film transistor of one pixel and its periphery), and FIG.
4 is a view showing a cross section taken along section line 4-4 of 4 (a cross-sectional view of a storage capacitor element portion). The reference numerals of each layer in the drawings are the first embodiment.
The description is omitted because it is the same as the matrix part.

This embodiment is an embodiment in which the present invention is applied to a liquid crystal display device having a simplified manufacturing process. In this embodiment, as shown in FIG. 14, the semiconductor layer AS of the TFT and the gate insulating film GI have substantially the same plane pattern. Therefore, the pattern formation of the semiconductor layer AS and the gate insulating film GI can be performed in the same step (step D in the first embodiment), and the pattern forming step of the gate insulating film GI described in the first embodiment (step E). ) Is unnecessary and the manufacturing process is shortened.

Also in the present embodiment, as shown in FIGS. 14 and 15, the opening SH of the protective film PSV1 is provided in the region between the pixel electrode ITO1 and the drain line DL. Therefore, by removing the conductive foreign matter by etching using the opening SH of the protective film PSV1 as a mask, the short circuit between the pixel electrode ITO1 and the drain line DL can be repaired.

Further, according to this embodiment, as shown in FIGS. 14, 16 and 17, the pixel electrode ITO1 and the gate line G are formed.
The opening SH of the protective film PSV1 is also provided in the region between L. Therefore, the conductive foreign matter is removed by etching using the opening SH of the protective film PSV1 as a mask, whereby the short circuit between the pixel electrode ITO1 and the gate line GL can be repaired. According to this embodiment, the gate line GL is covered with the anodic oxide film AOF, so that the pixel electrode ITO1
It is unlikely that the gate line GL and the gate line GL are short-circuited by a conductive foreign substance. However, if a pinhole is very rarely formed in the anodic oxide film AOF and a conductive foreign substance is present in that portion, a point defect defect occurs, so that there is an effect of preventing such a defect.

Since the alignment defect of the liquid crystal layer LC also occurs in the opening SH of the protective film PSV1 between the pixel electrode ITO1 and the gate line GL, as shown in FIGS. 16 and 17, on the second transparent glass substrate SUB2 side. The opening SH is covered with the light shielding film BM1.

<< TFT Substrate Side Light Shielding Film BM2 >> In the present embodiment, as shown in FIGS. 14 and 15, an opaque conductive film is formed on the periphery of the pixel electrode ITO1 of the first transparent glass substrate (TFT substrate) SUB1. The TFT substrate side light-shielding film BM
2 are provided.

This TFT substrate side light-shielding film BM2 has a function of a black matrix for blackening the periphery of the pixel electrode,
The effect of improving the display contrast is obtained.

By providing this TFT substrate side light-shielding film BM2, the aperture ratio of the liquid crystal display device can be improved.

Conventionally, the alignment margin of the first transparent glass substrate SUB1 and the second transparent glass substrate SUB2 is 5 μ on one side.
The first transparent glass substrate S has been required to have a length of m or more.
The alignment margin between the pixel electrode ITO1 on the UB1 and another conductive film, for example, d2 and d3 forming the drain line DL can be suppressed within 2 μm on one side.

Therefore, in the present embodiment, it is not necessary to shield the pixel electrode ITO1 more than in the case where only the light shielding film BM1 on the second transparent glass substrate SUB2 side covers the peripheral portion of the pixel electrode ITO1, and the aperture ratio is higher. Improved and the display screen becomes brighter.

Further, in this embodiment, the TFT substrate side light-shielding film B
Since the opening SH of the protective film PSV1 is provided between M2 and the drain line DL as shown in FIGS. 14 and 15, conductive foreign matter remains between the light-shielding film BM2 and the drain line DL. Even in this case, foreign matter in the opening SH can be removed by etching using the protective film PSV1 as a mask, so that a liquid crystal display device with high productivity is provided.

Further, in this embodiment, even if the light-shielding film BM2 and the drain line DL are simultaneously formed of the same metal film to simplify the manufacturing process, the short-circuited portion of the light-shielding film BM2 and the drain line DL is the protective film PSV1. Since it can be removed at the opening SH, the productivity is dramatically improved.

[Modifications] The present invention is not limited to the above-described embodiments, and various modifications can be considered.

18 to 29 are views for explaining various possible modifications of the present invention.

Since the reference numerals attached to the respective figures are the same as those of the matrix portion of the first embodiment, the description thereof will be omitted.

(Modification 1) FIG. 18 shows that the opening SH of the protective film PSV1 overlaps the pixel electrode ITO1 in a plane.
The case where the end portion of the pixel electrode ITO1 is exposed as shown in FIG. 26 is shown. However, the gate line G of the pixel electrode ITO1
The end portion adjacent to L has a protective film PSV1 as shown in FIG.
Covered with.

(Modification 2) In FIG. 19, the opening SH of the protective film PSV1 is formed not only between the pixel electrode ITO1 and the drain line DL as shown in FIG. 24, but also as shown in FIG. The case where it is also provided in the GL is shown.

(Modification 3) In FIG. 20, the opening SH of the protective film PSV1 is formed not only between the pixel electrode ITO1 and the drain line DL as shown in FIG. 26, but also as shown in FIG. The case where it is also provided in the GL is shown.

(Modification 4) FIG. 21 shows a case where the opening SH of the protective film PSV1 is provided on the entire surface of the pixel electrode ITO1 as shown in FIG. However, the pixel electrode ITO
The end portion adjacent to the first gate line GL is covered with the protective film PSV1 as shown in FIG.

(Modification 5) FIG. 22 shows a case where the opening SH of the protective film PSV1 is provided on the entire surface of the pixel electrode ITO1 as shown in FIG. Furthermore, the pixel electrode ITO
The end portion adjacent to the first gate line GL is also exposed from the protective film PSV1 as shown in FIG.

The modification described above is intended for a liquid crystal display device which can be manufactured by the same manufacturing method as the liquid crystal display device described in the first embodiment. The opening SH of the protective film of each modified example
May be applied, which has the effect of simplifying the manufacturing process.

[0130]

As is apparent from the above description,
According to the liquid crystal display device of the present invention, even if a so-called point defect occurs, a liquid crystal display device that can repair the defect can be provided, and a liquid crystal display device with high productivity can be provided.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a liquid crystal display substrate to which the present invention is applied.

2 is a cross-sectional view showing an embodiment of a liquid crystal display substrate to which the present invention is applied, and corresponds to a cross section 2-2 in FIG.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

4 is a cross-sectional view taken along line 4-4 of FIG.

FIG. 5 is an exploded perspective view showing an embodiment of a liquid crystal display device to which the present invention is applied.

FIG. 6 is an explanatory view showing an embodiment of the manufacturing method of the present invention,
It is sectional drawing which showed process AG.

FIG. 7 is an explanatory view showing an embodiment of the manufacturing method of the present invention,
It is a top view which showed process AG.

FIG. 8 is a diagram illustrating a situation in which a conductive foreign substance exists between a drain line and a pixel electrode in a liquid crystal display device to which the present invention is applied.

9 is a diagram illustrating a situation in which a conductive foreign substance exists between a drain line and a pixel electrode in a liquid crystal display device to which the present invention is applied, and is a cross-sectional view taken along the line DD ′ of FIG. 8.

FIG. 10 is a diagram illustrating a step (step H) of removing a conductive foreign substance existing between the drain line and the pixel electrode in the liquid crystal display device to which the present invention is applied.

11 is a diagram illustrating a step (step H) of removing a conductive foreign substance existing between the drain line and the pixel electrode in the liquid crystal display device to which the present invention is applied, which is taken along line EE ′ of FIG.
It is sectional drawing in a cross section.

FIG. 12 is a diagram showing a structure of a gate terminal applied to a liquid crystal display device of the present invention in comparison with an opening portion of a protective film.

FIG. 13 is a diagram showing a structure of a drain terminal applied to the liquid crystal display device of the present invention in comparison with an opening of a protective film.

FIG. 14 is a plan view showing a second embodiment of a liquid crystal display substrate to which the present invention is applied.

15 is a sectional view showing a second embodiment of a liquid crystal display substrate to which the present invention is applied, and corresponds to a section 2-2 in FIG.

16 is a cross-sectional view taken along line 3-3 of FIG.

17 is a cross-sectional view taken along line 4-4 of FIG.

FIG. 18 is a plan view showing a first modification of the liquid crystal display substrate to which the present invention is applied.

FIG. 19 is a plan view showing a second modification of the liquid crystal display substrate to which the present invention is applied.

FIG. 20 is a plan view showing a third modification of the liquid crystal display substrate to which the present invention is applied.

FIG. 21 is a plan view showing a fourth modification of the liquid crystal display substrate to which the present invention is applied.

FIG. 22 is a plan view showing a fifth modification of the liquid crystal display substrate to which the present invention is applied.

FIG. 23 is a cross-sectional view taken along the line aa ′ of FIGS. 18 and 21.

FIG. 24 is a cross-sectional view taken along the line bb ′ of FIG.

25 is a cross-sectional view taken along the line cc 'of FIG.

FIG. 26 is a sectional view taken along the line dd ′ of FIGS. 18 and 21.

FIG. 27 is a cross-sectional view taken along the line ee ′ of FIG.

FIG. 28 is a cross-sectional view taken along the line ff ′ of FIGS. 21 and 22.

FIG. 29 is a cross-sectional view taken along the line gg ′ of FIG.

FIG. 30 is a plan view showing a pixel portion of a conventional liquid crystal display substrate.

31 is a cross-sectional view showing a pixel portion of a conventional liquid crystal display substrate, which corresponds to a cross section taken along the line AA ′ of FIG. 30.

32 is a diagram illustrating a situation in which a conductive foreign substance exists between the drain line and the pixel electrode in the conventional liquid crystal display device, and is a cross-sectional view taken along the line BB ′ of FIG. 30.

[Explanation of symbols]

SUB1 ... first transparent glass substrate, SUB2 ... second
Transparent glass substrate, ITO1, ... Pixel electrode, PSV1 ...
... Protective film, TFT ... Thin film transistor (semiconductor switching element), SH ... Opening of protective film.

Claims (8)

[Claims] 1. A pixel electrode provided on a first substrate, a switch element, a video signal line for supplying a video signal to the pixel electrode via the switch element, and an insulating film covering the video signal line. A liquid crystal display device including a protective film, wherein an opening of the protective film is provided between the pixel electrode and the video signal line, and the video signal line does not exist in the area of the opening, and A liquid crystal display device, wherein an edge portion of the pixel electrode is covered with the protective film. 2. A pixel electrode provided on a first substrate, a switch element, a video signal line for supplying a video signal to the pixel electrode via the switch element, and conduction / non-conduction of the switch element. A liquid crystal display device comprising a scanning signal line for supplying a scanning signal for controlling the scanning signal line and a protective film made of an insulating film for covering the scanning signal line, wherein an opening of the protective film is provided between the pixel electrode and the scanning signal line. And a scanning signal line does not exist in the area of the opening, and the edge portion of the pixel electrode is covered with the protective film. 3. The video signal line is made of an opaque metal film provided on the first substrate made of a transparent insulator, and an edge portion of the pixel electrode is made of the same material as the video signal line. 2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is covered with a first light-shielding film, the first light-shielding film is covered with the protective film, and the first light-shielding film does not exist in the area of the opening. . 4. The scanning signal line is made of an opaque metal film provided on the first substrate made of a transparent insulator, and an edge portion of the pixel electrode is made of the same material as the scanning signal line. The liquid crystal display device according to claim 2, wherein the liquid crystal display device is covered with a first light-shielding film, the first light-shielding film is covered with the protective film, and the first light-shielding film does not exist in the region of the opening. . 5. A second light-shielding film, which is provided in a peripheral region of the pixel electrode and shields the switch element, is provided on a transparent second substrate facing the first substrate with a liquid crystal layer interposed therebetween. The liquid crystal display device according to claim 1 or 2, wherein the light-shielding film planarly covers the opening of the protective film. 6. A terminal, which is electrically connected to the video signal line or the scanning signal line, is provided on the first substrate, and the terminal is made of a transparent conductive film exposed from the protective film. The liquid crystal display device according to claim 1 or 2. 7. A drain terminal, which is electrically connected to the video signal line, is provided on the first substrate, and the drain terminal includes a metal portion made of a metal film exposed from the protective film.
The liquid crystal display device according to claim 1 or 2, wherein the liquid crystal display device comprises a transparent conductive film that covers the metal portion. 8. A gate terminal, which is electrically connected to the scanning signal line, is provided on the first substrate, and the gate terminal includes a metal portion made of a metal film exposed from the protective film, and the metal portion. The liquid crystal display device according to claim 1 or 2, wherein the liquid crystal display device is formed of a transparent conductive film that covers the.